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ANALYSIS OF PEER-TO-PEER
SOCIAL NETWORKING
Afrin Shaik
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OUTLINE
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Problem
Introduction
Related work
My contribution
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Problem
As social networking analysis, peer-to-peer social networking
analysis is also interesting in terms of
• Data availability and long term data durability.
• How many peers are online and for how much time?
• How can we maintain replicas, how those replicas available to
other peers.
• How many replicas are selected to store a single profile.
• What are the criteria to select replicas.
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Introduction
• What is social networking?
• Facebook, My space, Twitter, etc….
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• Basic structure of OSN
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Social networking
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In social networking owner has access to all
the data.
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Using this data these networks filters the
advertisements based on interests of
individuals and displays them.
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Social networking
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Social networking
• Client server architecture
• Huge amount of personal information
• User must trust their providers blindly
• Some limitations like
-privacy concerns.
-requirement of internet connectivity.
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What is Peer-to-Peer social networking?
• To overcome these issues peer-to-peer architecture is proposed
for the social networks called peer to peer social networking.
• paradigm shift from client-server to a peer-to-peer infrastructure
coupled with encryption so that users keep control of their data
and can use the social network also locally, without Internet
access.
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Peer to peer social networking
• Peer to peer resembles real life
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• Social relations of the users are maintained by including three
attributes – “unique iden-tifier/pseudonym”, “relation-type”
(friend, relative, colleague, etc.) and “trust level” (High,
Medium, Low).
• The profiles of the users are divided into two main categoriesResources and Relations.
• The social links of a user are divided into groups based on the
relation-type attribute and are stored under the category,
Relations.
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• The category, Resources is also divided into groups based on types,
such as private in-formation (Profession, age, educational
qualification, family information, etc.) private messaging, public
messaging (wall, group page, status, events, etc.), pictures or
videos, etc.
• Access control constraints on resource or group of resources are
defined, to specify specific operation type, such as read, or write
on the wall, or status (public messaging); view, or comment, or tag
on pictures, or videos; or read, write, administration on grouppages or events.
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P2p Social networking
• Two approaches of p2p Social Networking.
- MyNet
- PeerSoN
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MyNet
• This approach provides secure p2p social networking service
on top of unmanaged internet Architecture(UIA) overlay.
• The focus is on providing resources among friends and devices
uniformly and without delay.
• MyNet enables users to share the data in a secure fashion
with his/her friends or colleagues.
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peerSoN
• This approach paid attention to security and privacy concerns.
• Main goal is to remove centralized entities.
• This is achieved by using DHT.
• To increase the availability replication technique is used.
Clients cache all the entries received and make them available
to other peers.
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Prototype architecture(peerSoN)
• Lookup service – meta data
required to find users and
the data they store ( IP
address, informaion about
files and notification for
users)
• Peers and user data such as
user profiles
• PeerSoN uses Distributed
Hash Tables for Look up
service
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Storage in peer-to-peer social networks
• Long term durability of content.
• online availability.
• bootstrapping.
• # friends.
• Geography.
To store small objects peerSoN uses replication technique rather than
coding.
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Related Studies
Replica Placement in P2P Storage: Complexity and
Game Theoretic Analyses
By Krzysztof Rzadca, Anwitaman Datta, Sonja Buchegger.
• They have studied replica placement in a p2p storage system in order to
optimize availability and the number of replicas.
• Analyzed two idealistic models of peer availability : probabilistic model; and time
slot model. For both models, they proved that it is NP-hard to optimize
availability for the socially-equitable scheme (in which the data availability of all
peers is similar).
• The performance for less available peers can be improved by considering diurnal
patterns of peer availability, rather than just a single number. However, exploiting
diurnal patterns has a measurable impact only when the system has truly global
scope, gathering participants from different time zones
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Another study
Geographic routing in social networks
By David Liben-Nowell, Jasmine Novak, Ravi Kumar, Prabhakar Raghavan, and
Andrew Tomkins
• They have shown that the natural mechanisms of
friendship formation result in rank-based friendship:
people in aggregate have formed relationships with
almost exactly the connection between friendship and
rank that is required to produce a navigable small world.
In a lamentably imperfect world, it is remarkable that
people form friendships so close to the perfect
distribution for navigating their social structures.
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In-degree (Left) and out-degree (Right) distributions in LiveJournal. For each k, the
number Nin(k) of LiveJournal users who are listed as a friend of at least k users and
the number Nout(k) of people who list at least k friends are shown, both for all
1,300,000 users and the 500,000 users who list locatable hometowns in the United
States.
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The relationship between friendship probability and
geographic distance. (A) For each distance , the
proportion P() of friendships among all pairs u, v of
LiveJournal users with d(u, v) is shown. Distances
are rounded down to multiples of 10 km. The
number of pairs u,v with d(u, v) is estimated by
computing the distance between 10,000 randomly
chosen pairs of people in the network. The curved
line corresponding to P() 1 in A models the fact
that some LiveJournal friendships are independent
of geography: for distances larger than 1,000 km,
the background friendship probability begins to
dominate geography-based friendships. (B) The
same data are plotted, correcting for the background
friendship probability: we plot distance versus P()
5.0 106.
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The relationship between friendship probability and rank
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My contribution
• Analyze replica management in terms online availability, and
unavailability of peers by considering geography into account.
• Data
- Simulations
• Network Metrics
- Power law distribution.
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Questions
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References
Robayet Nasim. Privacy-Enhancing Access Control Mechanism in Distributed Online Social
Network. KTH Master's thesis, May 2011.
Krzysztof Rzadca, Anwitaman Datta, Sonja Buchegger. Replica Placement in P2P Storage:
Complexity and Game Theoretic Analyses. In Proceedings of ICDCS 2010, Genoa, Italy, June
2010.
Sonja Buchegger, Doris Schiöberg, Le Hung Vu, Anwitaman Datta. PeerSoN: P2P Social
Networking - Early Experiences and Insights. In Proceedings of SocialNets 2009, The 2nd
Workshop on Social Network Systems, Nuernberg, Germany, March 31, 2009.
Doris Schiöberg. A Peer-to-peer Infrastructure for Social Networks. Diplom Thesis, TU Berlin,
Berlin, Germany, Dezember 17, 2008.
Sonja Buchegger, Anwitaman Datta. A Case for P2P Infrastructure for Social Networks Opportunities and Challenges. In Proceedings of WONS 2009, The Sixth International
Conference on Wireless On-demand Network Systems and Services, Snowbird, Utah, USA,
February 2-4 2009.
Onnela J-P, Arbesman S, Gonza´lez MC, Baraba´si A-L, Christakis NA (2011) Geographic
Constraints on Social Network Groups. PLoS ONE 6(4): e16939.
oi:10.1371/journal.pone.0016939
Facebook and Online Privacy: Attitudes, Behaviors, and Unintended Consequences
Geographic routing in social networks By David Liben-Nowell*†‡§, Jasmine Novak†, Ravi
Kumar†¶, Prabhakar Raghavan¶, and Andrew Tomkins†¶
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